I let them design them (pick out the main beads and the order of the beads) and then I wired them up: I also let them pick the small beads when they wanted to - and I filled in where it looked right w/more small beads.
Here are the boys showing off their very nice designs:
Carson went with an orange and blue design... with red wire.
Lucas did a "mostly blue, green is okay, like green green green, blue, blue blue" with black wire.
They actually watched me make most of the bracelets! That was cool that they were so interested. They also both raced across the street to their home to show their mom the second their bracelet was done, heh. Very cool.
I actually made them big enough that they can take them on and off without doing the toggle, and it's wirey so they won't just "fall off" unnoticed.. plus then they can wear them pretty much until they grow up - maybe even then if they decide to take care of the bracelets (I'm not holding my breath, heh).